Bill, I use the on-camera flash for the E10. I don't know the guide number offhand but I usually use the flash for photos up to about 15 feet. Because of the increased shadow detail you seem to get with digital, it's probably good for quite a bit more with print manipulation in the digital darkroom. My friend, the photojournalist, uses the E10 with a Vivitar 285 and thinks the combination is fantastic. On other thing about the E10/20 is that it has a PC connector so you can shoot a studio flash unit. This is perhaps the least expensive digital camera with this fitting. It is said, but I cannot tell you due to a total lack of experience, that the Olympus FL-40 is the best way to go. But I have been very happy with no more than the built-in flash unit. It suits my needs well enough. cheers, rand ferret@wyoming.com -------Original Message------- Rand, Your comments have been most helpful. The E20 is definitely one choice being considered. In regard to a flash, are you using the Olympus dedicated flash. And if not, what are you using with the E-10. I shoot weddings for a local Chicago area studio for which I want the E-20. Thanks again, Bill Ellis wb9cac@attbi.com